Microwaves seem to be feared by so many people because people generally don't really know what's going on in that big, humming box. But the fact is, microwaves heat food just like anything else (frying, baking, boiling). I'm just getting interested into raw foods, so I've been studying these things recently. Cooking foods tends to reduce their vitamin and overall nutrient content (with some exceptions), alters the structure of the protein, and forms various carcinogens (acrylamide, HCAs, PAHs). Like I said, there are some exceptions in the reductions of vitamins and antioxidants. Cooked tomatoes have an increased concentration and bioavalability of lycopene, and peanuts have higher concentrations of antioxidants after being roasted, for example. But generally, more vitamins and nutrients remain in foods in their raw state.